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Published on: December 22, 2018
Convective cells and blob control in a simple magnetized plasma
1Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association Euratom-Confédération Suisse, Lausanne, Switzerland.
Physical Review Letters
|March 10, 2012
Summary
Researchers controlled plasma blobs in magnetized toroidal plasmas by creating convective cells with biased electrodes. This method allows for significant variation in blob velocities and offers insights into plasma dynamics.
Area of Science:
- Plasma Physics
- Fusion Energy Research
- Magnetohydrodynamics
Background:
- Plasma blobs are common in magnetized plasmas and can affect confinement.
- Controlling these blobs is crucial for understanding and improving plasma stability in fusion devices.
Purpose of the Study:
- To demonstrate blob control in magnetized toroidal plasmas using biased electrodes.
- To investigate the formation and properties of convective cells for plasma manipulation.
- To analyze the impact of different biasing schemes on plasma blob dynamics.
Main Methods:
- Utilized a two-dimensional electrode array on a metal limiter in a magnetized toroidal plasma.
- Performed detailed two-dimensional cross-field measurements.
- Implemented various biasing schemes to induce convective cells.
Main Results:
- Successfully demonstrated the formation of a uniform convective cell along the magnetic field.
- Showed that radial and vertical blob velocities can be significantly altered by biasing schemes.
- Observed that cross-field currents limit potential variations, with strongest variations shifted from the biased region.
Conclusions:
- Biased electrode-induced convective cells are an effective method for controlling plasma blobs.
- Plasma flow dynamics and cross-field currents play a critical role in potential variations and blob control.
- This technique offers a pathway for improved plasma confinement and stability in fusion research.
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